package priv.pront.code.mati.province.comp;

import java.util.Scanner;

/**
 * @Description:
 * @Author: pront
 * @Time:2023-11-18 14:35
 */
public class Main6 {

    static int n;
    static String s;
    static StringBuilder sb = new StringBuilder();
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        n = scanner.nextInt();
        s = scanner.next();
        sb.append(s.charAt(0));
        int idx = 1;
        int nal = 0;
        while(idx < s.length()) {
            if(nal == n - 1){
                sb.append(s.charAt(idx));
                nal = 0;
            }else{
            nal++;

            }
            idx++;
        }
        System.out.println(sb.toString());
    }
}
